Tape feed mechanism



Nov. 5, 1963 Filed NOV. 9, 1959 J. B. GRAY TAPE FEED MECHANISM v llSheets-Sheet l Nov. 5, 1963 I J. B. R 3,109,898

- TAPE FEED MECHANISM V.

Filed Nov. 9, 1959 l1 Sheets-Sheet 2 f/ec/rarr/c 671144901910 -jWeaken/my Nov. 5, 1963 J. B. GRAY 3,10

TAPE FEED MECHANISM Filed 1959 l heets-Sheet 3 Nov. 5, 1963 J. B. GRAY3,109,898

TAPE FEED MECHANISM Filed Nov. 9, 1959 ll Sheets-Sheet 4 wo k Nov. 5,1963 J. B. GRAY TAPE FEED MECHANISM 11 Sheets-Sheet 5 Filed Nov. 9, 1959mn awraxu Jab 5. 6/17- J. B. GRAY 3,109,898

TAPE FEED MECHANISM ll Sheets-Sheet 6 Ill. IIIIIIII ll-I'll [llll-l.

Nov. 5, 1963 Filed Nov. 9, 1959 f xmn hmm k Nov. 5, 1963 J. B. GRAY3,109,398

TAPE FEED MECHANISM Filed Nov. 9, 1959 ll Sheets-Sheet 7 w wi Nov. 5,1963 J. B. GRAY TAPE FEED MECHANISM 11 Sheets-Sheet 8 Filed Nov. 9, 1959NRMMMNN m ma Nov. 5, 1963 J. B. GRAY TAPE FEED MECHANISM ll Sheets-Sheet9 Filed Nov. 9, 1959 E ENE P Q Nov. 5, 1963 J. B. GRAY TAPE FEEDMECHANISM ll Sheets-Sheet 10 Filed Nov. 9, 1959 Nov. 5, 1963 J. B. GRAYTAPE FEED MECHANISM ll Sheets-Sheet l1 Filed NOV. 9, 1959 m m RR UnitedStates Patent 3,109,898 TAPE EEE MEQHANISM .lohn B. Gray, Los Angeles,Calif., assignor to Packard- Eeil Eiectronies Corporation, Los Angeles,Calif., a corporation of California Filed Nov. 9, 1959, Ser. No. 851,70519 Ciaims. (Cl. 1791fi9.2)

This invention relates to recording and reproducing equipment and, moreparticularly, to multi-channel recording and reproducing equipment whichutilizes a number of magnetic tapes.

There are many applications in which continuous recording of a number ofsignals is required over a relatively :long period of time. During thisrelatively long period of time, it may be desirable to reproduce or playback a portion of the recorded signals. When continuous magnetic tape isutilized as the recording medium, a substantial interval may elapse tohunt for the portion to be reproduced. For example, the apparatus may berequired to record eight hours of continous information and after sevenhours of recording, it is desired to play back the signals recordedduring the first hour. In conventional recording and reproducingequipment, it is necessary to rewind the magnetic tape to the portionutilized for recording the first hour of information. 'For manyapplications, such a delay is highly undesirable.

Moreover, in some applications, it is desirable not to interrupt therecording sequence in order to reproduce portions of the alreadyrecorded information. For such applications, the utilization ofconventional equipment which records the information on a continuousmagnetic tape is impossible.

In a specific illustrative embodiment of this invention, a number ofmagnetic tape magazines are utilized for successively recording theinput information in a number of different recording channels. Therecording and reproducing appartus may, for example, be utilized in anaircraft to provide a continuous recording of diiferent characteristicsof the aircraft in the different recording channels. The recording iscontinuous with the magazines automatically becoming operative insuccession.

Features of this invention relate to the provision of control means forsuccessively operating the magazines to provide for a continuousrecording of the input information. Each of the magazines includes aninternal pinch roller for engaging the magnetic tape. A drive capstancommon to all of the magnetic tape magazines, is continuously rotatedand the magazines become operative when these internal pinch rollersengage the magnetic tape between the pinch roller and the rotatingcommon capstan. The pinch rollers are individually controlled byassociated solenoids which are part of the control means. Theutilization of an internal pinch roller, which is remotely controlled,is an important feature of the invention.

When information is being recorded on the tape in any magazine, theinformation recorded in any other magazine may be reproduced withoutinterrupting the recording sequence. Moreover, means are provided forreproducing the information recorded on a tape which is still beingutilized for recording the input information. This feature isaccomplished by utilizing a standby magazine to which the inputinformation is switched when the information to be reproduced is on thesame tape which is receiving the input information. At the end of thereproducing sequence, the input information is switched back to theoriginal tape which was recording the information. The searching time tofind any portion of the recorded signals and to begin reproducing thesignals is quite brief, less than 30 seconds, even when a switchingsequence is required to the standby magazine.

Patented Nov. 5, 1953 Other features of this invention pertain to theprovision of means for recording a control tone below the frequency bandof the input signfls to be recorded. The low frequency control tone iscontinuously recorded with the input signals and is utilized to find theend of the recorded signals on the original tape. When the input signalsare switched back to the original tape at the end of the reproducingsequence, they are recorded on the portion of the original commencing atthe end of the previously recorded signals. When the reproducingsequence is terminated a high-speed reeling sequence is initiated for10- cating the termination of the recorded signals on the original tape.During the high speed reeling the control tone is effectively multipliedto a frequency detectable by amplifier means which controls theswitching operation.

iFurther features of this invention relates to the provision of meansfor briefly recording a tone of predetermined frequency on the magnetictape as an indication that the input information is being switched tothe standby tape. The tone is also briefly recorded on the standby tapeto indicate that the input information is being switched back to itsoriginal tape.

The entire recorded information, including the information on thestandby tape, may be reproduced in proper sequence after recording iscompleted. The tapes are automatically reproduced one after another,with the detection of the briefly recorded tone initiating a switchingoperation to the standby tape. The reproducing sequence is uninterruptedwith the information being supplied from the standby tape instead of thetape including the briefly recorded tone. When the briefly recorded toneon the standby tape is detected, the switching sequence is reversed sothat the information is reproduced again from the original tape. in thismanner, the reproducing sequence of the entire recorded information isautomatic.

Further features and advantages of this invention will become apparentupon consideration of the following description when read in conjunctionwith the drawing wherein:

FIGURE 1 is a pictorial view of a control panel which may be remotelylocated and which is utilized for controlling the operation of therecording and reproducing apparatus of this invention;

FIGURE 2 is a pictorial view of the main unit of the recording andreproducing apparatus of this invention with a portion of the uppermagazine and control mechanism removed;

FIGURE 3 is a pictorial view of one of the tape magazines utilized inthe recording and reproducing appartus of this invention;

FIGURE 4 is a pictorial view of the main unit of the recording andreproducing appartus of this invention with a portion of the unitremoved and illustrating in particular some of the tape controlmechanism;

FIGURES 5 through 12, when arranged in accordance with the FIGURE 13,are a circuit representation of the recording apparatus of thisinvention; with FIGURE 5 being a circuit representation of the controlpanel;

FIGURE 6 being a circuit representation of the electronic equipmentsection of the main unit; and

FIGURES 7 through 12 being a circuit representation of the controlmechanism portion of the main unit; and

FIGURE 13 is a diagram illustrating the arrangement of FIGURES 5 through12.

The recorder and reproducer of this invention includes four maincomponents: (1) a remote control panel 16 which is depicted in FIGURE 1;(2) a magazine control mechanism 18 which is depicted in FIGURES 2 and4; (3) a tape magazine section 29 depicted in FIGURES 2 and 3; and (4)electronic equipment 19 depicted in FIG URE 2. The magazine section 29,the control mechanism and the electronic equipment 19 together form amain package shown in FIGURE 2 which may illustratively have thedimensions of 12% inches wide, 6 /2 inches high and 18 inches deep, andit may weigh approximately 33 pounds. The tape recorder providesillustratively for eight hours of recording time with the recording tapebeing in four separate parts in'four magazines 35, 36, 37 and 38included as part of the magazine section 29. The four magazines through38 and a standby magazine 3? are utilized in the illustrative embodimentof this invention being positioned one on top of another in compartmentsof the magazine section 29. The specific em bodiment of this inventionis described with reference to the five magazines 35 through 39. Alarger or smaller number of magazines may be utilized. The overalldimensions of each of the magazines may be 10 inches long, 6 /2 inchesWide and 1 /2 inches high. Release buttons 35a through 39a on the frontof the respective magazines 35 through 39 control latching mechanism notshown which is conventional to permit the easy removal of the magazinesfrom the magazine section 29.

As is hereinafter described and as depicted particularly in FIGURE 3,the various control elements in each of the five magazines 35 through 39are at a minimum. The five magazines 35 through 39 are similar andequipment such as the recording heads 21!) through 214, the reproducingheads 450 through 454, the erasing heads 7S0 through 794 and thesolenoids 355 through 3% are all external to and not part of themagazines 35 through 39. These components are all described in detailduring the description of the operating sequences of the apparatus. Inorder to illustrate the simplicity of the magazines 35 and 39, atabulation of the main components included in the magazine 35 is givenbelow. These components are also described in detail during thedescription of the operating sequences of the apparatus. The tabulationindicates that the control elements for moving the tape and recordingand reproducing signals on the tape are all external to the magazines.

(1) A magnetic tape 68 which may be 1,200 feet long, /1, of an inch wideof the type 2 mil Mylar tape;

(2) A take-up reel 34 and a rewind reel 33;

(3) A pair of fine-pitch gears 34a and 33a at the base of the reels 34and 33 respectively for connecting the reels to an external drivingsystem when the magazine is in position;

(4) A tape position counter 350, which is driven by a counter gear traincoupled to the tape to provide a numerical indication through a window(FIGURE 2) on the magazine 35;

(5) Tape end switches 22d) and 360, not shown in FIGURES 2 and 3, whichare controlled by metal-foil strips, also not shown, on the magnetictape 68 to indicate when the respective ends of the tape are reached;

(6) A rotatable capstan pinch roller 66 which is rotated by the externalsolenoid 358;

(7) A magazine release mechanism, not shown, controlled by the releasebuttons 35a (FIGURE 2);

(8) Tape guides 35D; and

(9) An electrical connector 35E.

As indicated above, these nine components will be further describedduring the description of the operating sequences of the recording andreproducing apparatus of this invention.

The various components of the magazines 35 through 39 and of the rest ofthe recording and reproducing apparatus are described with reference tofour operating sequences of the apparatus:

( 1) Continuous recording;

(2) Playback of one magazine while recording in another;

3) Simultaneous recording and playback of the same magazine; and

(4) Automatic playback.

4 Continuous Recording The recording and reproducing apparatus of thisinvention may be operated to provide for a continuous recording of inputinformation on the five magnetic tapes of the tape magazines 35 through39. To initiate the operation of the recording and reproducing apparatusto provide for the continuous recording sequence, a power button 30 onthe control panel 19 illustrated in FIGURE 1, is first depressed. Thepower button 313 which is also depicted in FlGURE 5, closes and latchesa path from a power source 35 to energize a power relay 3913. The relay36B remains energized until the button 39 is again depressed or until itis released at the end of the continuous recording sequence. FIGURE 5,which forms part of the circuit arrangement of the recording andreproducing apparatus of this invention depicted in FIG- ures 5 through12 when arranged in accordance with FIG- URE 13, is a circuitrepresentation of the control panel 1%). FIGURE 6 is a functionalarrangement of most of the electronic equipment 1?, and FZGURES 7through 12 are a circuit representation of the control mechanism 18.

The operation of two armatures 36A and 33C of the power relay StlBenergizes essentially the entire recording and reproducing apparatusexcept for the electronic equipment 1? depicted in FIGURE 6. Theequipment 19 is energized, as is hereinafter described, when a recordbutton 13 on the control panel It is depressed. More particularly, whenthe power relay 3GB is energized, it energizes three motors 50, 51 and52 in the control mechanism 18 (FIGURE 4) over an operating path throughthe armature 39C. The source 33 may provide volt-400 cycle power throughthe armature 343C and 28 volts direct-current through the armature 30A.The motor 54 is the drive motor for rotating a capstan 62 by means of agear linkage 63.

The driver motor 5 1 may be a 409 cycle synchronous motor which iscoupled by the gear linkage 6:3 to a fly wheel assembly 63F and to thecapstan shaft 62. A mechanical filter, not shown, in the output of thegear linkage 63 reduces the flutter content of the drive. The capstanshaft 62 is rotated at an illustrative speed of 71.6 revolutions perminute to provide, as is hereinafter described, for a tape recordingspeed of 178 inches per second. The capstan 62 is positioned adjacentall five of the magazines 35 through 39 which form part of the magazinesection 29. None of the five magnetictapes 68 respectively included inthe magazines 35 through 39 are, however, moved just due to the rotationof the capstan shaft 62'. The capstan shaft 62 continues to rotate aslong as power is supplied through the armature 30C of the power relay3013. The magazines 35 through 39 may be individually energized or anycombination thereof may be energized as is hereinafter described.Moreover, the direction of movement and the speed of movement of thetapes in different magazines may be diiIerent.

As indicated above, in addition to the tape drive motor 59, the powerrelay 3913 also energizes two motors 51 and 52. The motors 51 and 52 arethe reel drives for rotating respectively the five payout or rewindreels 33 and the five take-up reels 34. As tabulated above, each of thefive magazines 35 through 39 has a payout reel 33 and a take-up reel 34.Each of the motors 51 and 521 may be similar to the motor 5t} being a400 cycle induction motor. The motors 51 and 52 respectively driveoutput shafts through gear trains. The output shaft of the motor 51supports five fluid magnetic clutches 35R through 39R, which areindividually associated with the magazines 35 through 39, and the outputshaft of the motor 52 v supports five fluid magnetic clutches 3515through 39F, which are also individually associated With the magazines.35 through 39.

Each of the clutches 35R through 391?. and 35F through. 39F supports agear for engaging an. associated reeling gear train in the magazines toprovide a direct coupling.

to the associated reels. In FIGURE 3, the payout reel 33 of the magazine35 is driven by a gear 33A and the takeup reel 34 is driven by a gear34A. The gears 33A and 34A mesh respectively with gears on the magneticclutches 35R and 35F in FIGURE 4 when the magazine 35 is in position inthe magazine section 29.

The amount of power transmitted to the reels 33 and 34 in each of themagazines 35 through 39 is determined by the energization of theirassociated magnetic clutches. When power is turned on by the button 39,the magnetic clutches 35R and 35F are energized for the normal drivecondition and the rest of the magnetic clutches 36R through 39R and 36?through 3% are in a braking condition so that their associated reels donot rotate. The fluid clutches 35R and 35F are energized at the sametime that the solenoid 35S (FIGURES 3 and 4) associated with magazine 35is energized.

The solenoid 358 is one of five solenoids 358 through 393 which areindividually associated with the five magazines 35 through 39. Thesolenoids 358 through 398 are part of the control mechanism 1-8 and are,therefore, external to or not part of the magazines 35 through 39. Thesolenoid 355 is positioned adjacent a pivoted arm 65 (FIGURE 3) of theinternal pinch roller 66 of the mags.- zine 35. The pinch roller 66 isan internal pinch roller in that it forms part of the magazine 35 and ison the opposite side of the magnetic tape 68 as is the rotating capstan62. The pinch roller 66 rotates in a clockwise direction to pinch orengage the magnetic tape 68 between the roller and the rotating capstanshaft 62. With only the solenoid 358 of the five solenoids 35S through398 energized, only the tape 68 in the magazine 35 is driven by thedrive motor 59.

The five drive solenoids 35S through 398, the five magnetic clutches 35Rthrough 39R and the five magnetic clutches 35F through 39? arefunctionally depicted in FIGURE 10. The five drive solenoids 358 through395 are individually connected to the five terminals 1 through 5 of apole or deck 193K. The pole 1-3K is one of ten poles of .a waferstepping switch 103. The control mechanism 18, which is depicted inFIGURES 7 through 12, includes a number of similar wafer switches whichcan be stepped from position to position. The water switch 1G3 is arecord magazine selector switch in that it is set at a positioncorresponding to the magazine which is being utilized to record theinput information. At the initiation of the recording sequence, themagazine selector switch 1113 is set at position 1 to indicate themagazine 35 is being utilized. A conductive path is, therefore, providedfrom the solenoid 355 through terminal 1 of the pole 103K but not fromthe other four solenoids 363 through 398. The path from the solenoid 35is through the pole 193K, a lead 209, a normal armature of a relay 127,a power lead or line 261 and the power armature 36A to the source 33.When the power relay 3% is operated, the solenoid 358 is thereforeenergized to rotate the pinch roller 66 in the magazine 35 so as todrive the magnetic tape 63 of the magazine 35.

The live rewind clutches 35R through 39R are connected respectively tothe five terminals 1 through 5 of the pole 18311 of the magazineselector switch 103, and the five take-up clutches 35F through 39F areconnected individually to the five terminals 1 through 5 of the pole103] of the switch 193. The armature of the poles 1931-1 and 103] aremultipled through the lead 2% to the source 33 over the same pathdescribed above for the solenoid 358, so that the clutches 35R and 35Fare energized. With the clutches 35R and 35F and the solenoid 35Senergized, the magnetic tape 68 of the magazine 35 is driven at a speedof 1% inches per second adjacent the recording head 2 11} of the controlmechanism 18. The recording head 21% is a composite wafer structure ofeight heads =1 through 8 and is individually associated with themagazine 35. Corresponding composite heads 211 through 2.14 areindividually associated with the 6 magazines 36 through 39. Each of thecomposite heads 219 through 214, also depicted in FIGURES 9 and 12, haseight recording heads 1 through 3 because eight channels are recorded onthe magnetic tape 68. The present invention is not restricted to anynumber of channels as it is apparent that more or less may readily beutilized Though the tape 68 in the magazine 35 begins moving when thepower button 30 is depressed, signals are not introduced to therecording head 21% so that actual recording does not commence just bydepressing the power button 30. In order to initiate the actualrecording of the input information, a record button 31 (FIGURES l and 5)on the control panel 1% is closed. The record button completes a pathfrom the power source 33 through armature 313A of the power relay 3413to energize a record relay 31A.

One terminal of the winding of the relay 31A is connected to the button31 and the other to a grounded resistor 24-1. The button 31 latchesoperated and may be released by depressing it again. When the relay 31operates, it completes a path for the 400 cycle voltage from the source33 through the operated armature 311C and the now operated armature 31Cto a clock mechanism 10T. The clock mechanism 1llT provides anindication through windows on the control panel 16 of the elapsedduration of the recording sequence and the time remaining to record.

When the relay 31 operates, it also closes a path from the source 33through armature 30A of relay 3013, the power lead 20d and the powerlead 200 through armature 31B of the record relay 31A to eight recordingamplifiers 71 through 78 (FIGURE 6) to a side tone amplifier 61, to atone generator 802., and also to a bias oscillator 62. The recordingamplifiers 71 through 78 are energized in this manner to amplify inputsignals respectively received through eight leads 81 through 88. Theamplifiers 71 through 7 8 may be conventional type amplifiers utilizedfor reconding electrical signals on magnetic tape. Eight recordingamplifiers 7-1 through 78 are provided because as indicated above, eightchannels of information are recorded on each of the magnetic tapes 68.

The amplified signals from the recording amplifiers 71 through 78 arerespectively provided through the poles 113A through 11311 to the eightrecording heads 1 through 8 of the composite recording head 210. Thereare five composite heads 210 through 214, as described above, andillustrated in FIGURE 4, which are respectively positioned adjacent themagnetic tapes 68 in the magazines 35 through 39. Each of the recordingheads 210 through 214 may be a sandwich or wafer arrangement includingeight recording heads for providing the eight longitudinal channels ofrecorded information on the magnetic tape 68. The poles 113A through11311, inclusive, are part of a record head selector switch 113 whichoperates together with the recording magazine selector switch 103. Bothswitches are always at the same position. At the initiation of thecontinuous recording sequence, the switches 1113 and 113 are both atposition 1.

The tone generator 832, which is energized with the record relay 31A,provides a 50 cycle per second tone to the input lead 81. The 50 cycletone insures the continuous recording of signals in the first channel.The 50 cycle tone is below the pass band of the input audio signals andso it does not interfere with normal recording or reproducing of thesignals. As is hereinafter described, the 50 cycle tone is utilizedduring high speed reeling of a tape 68, to locate the termination pointof the recorded signals on the tape. This high speed reelingautomatically occurs after a standby recording sequence utilizing themagazine 39.

The signals from the amplifier 78 are provided to an overload indicator121 on the panel 10 as well as to the composite head 210. The indicator12.1 provides a visible indication to the operator of the output levelof the signals to the composite recording heads 21%. A gain control dial4% (FIGURE 1) on the control panel 19 may be rotated to adjust the gain.The dial 46* controls the setting of a potentiometer 4913 which iscoupled in a biasing circuit from the power source 33 to the eightamplifiers 71 through 78. The gain of all eight amplifiers may, in thismanner, readily be adjusted.

The recording sequence continues in this manner with the signals throughleads '81 through 88 being respectively recorded by the heads 1 through8 of the composite magnetic head 21% along longitudinal tracks of thetape 68 (FIGURE 3) of the magazine 35. The other four magnetic tapes 68in the magazines 36 through 39 are stationary at this time.

The input signals recorded in each of, the tracks of the tape 63 may beaudio frequency signals in the range from 200 to 4,000 cycles persecond. A sidetone amplifier 61 is provided which is coupled to each ofthe recording amplifiers 71 through 78 so that the signals be ingrecorded can be listened to.. The amplifier 61 is coupled through aswitch to output circuits 61A which may include a speaker. The outputfrom the amplifier 61 may, illustratively, have a maximum magnitude of 3volts and present an impedance of 75 ohms. Supersonic bias is utilizedwhich is supplied fromthe bias oscillator 62.

The oscillator 62 also can be utilized to erase the signals recorded onany of the tapes 68. A switch 8%,

i which is not on the control panel 16, is open during the continuousrecording sequence so that erasure does not take place. The erasuresequence is hereinafter described.

At the end of the magnetic tape 68' in the magazine 35, the controlmechanism 18 automatically steps the input signals to the compositemagnetic head 211 which is positioned adjacent the magnetic tape 68 ofthe magazine 36 instead of the composite head 219. The magazine 36 isalso automatically energized and the magazine 35 is de-energized toswitch the recording sequence from the magazine 35 to the magazine 36.Toward the end of the magnetic tape 68 in the magazine 35', a metallicmember, not shown, carried by the tape 68, operates the tape end switch221 which is individually associated with the magazine 35. There arefive tape end switches 22%) through 224 which are individuallyassociated with the magazines 35 through 39 and which are shownfunctionally in FIGURE 10. When the tape end switch 220 is closed, itcompletes a path from the power lead 201 through the switch 220, throughcable 225 and cable 226 to terminal 1 of the pole 103A of the recordmagazine selector switch 103. The armature of the pole 103A is connectedthrough to the interrupter 103T of the switch 103. When the tape endswitch 225 is operated, it therefore energizes the record magazineselector switchw103, and also the record head selector 213 by means of aconnection through the lead 23h from the winding of the switch 226. Thetwo switches 103 and .1 13 are operated, in this manner, in parallel.When the selector switches 1G3 and 113 are energized, they are steppedfrom position 1 to position 2. The record magazine selector switch 1%selects the magazine 35 instead of the magazine 35 and the selectorswitch 113 selects the composite magnetic head 211 instead of thecomposite magnetic head 21% for recording the input information. 1 IRewind clutch power is delivered through the pole 10311 to the magneticclutch 36R, take-up clutch power is delivered through the pole 163] tothe magnetic clutch 36F and the end of tape relay 127 to the magneticclutch 36R and drive solenoid power is delivered, as described above,through the pole 183K to the solenoid 36R. As the armatures of poles1631-1, 133 and 103K step from position 1 to position 2, they alsoremove power from the clutches 35R and 3536 and from the solenoid 358 sothat the tape 63 and the reels 33 and 34 in the magazine 35 are halted.

The sequence continues in this manner with magazine after magazine beingenergized until the tape end switch 224 is 'operated at the end of themagnetic tape 68 of the magazine 39. As is hereinafter described, themagazine 39 may \be utilized during the playback sequence for recordinginput signals. During the continuous recording sequence, only theremaining unrecorded portion of the tape 68 in the magazine 39' isutilized. When the switch 224 is operated at the end of the tape $3 inthe magazine 39, it energizes the end of tape relay 127 and a resetrelay 118 to halt the recording sequence and turn oil the powerreturning the recording and reproducing apparatus to normal. Theoperating path for the relay 127 is from the switch 224, through pole1936 and lead 23%) to the winding of relay 127. The operating paththrough lead 230 is also extended through a lead 235. to the wind ing ofthe reset relay 118 causing it to operate.

Vhen the relay 127 operates, it extends a connection from the power line201 through its operated armature and contact 2 to the lead 231 tolockthe record reset relay 118 in its operated condition. The relay 127 isalso locked-operated by the locking path through its operated armature.When the record reset relay 118 operates, it returns the record magazineselector switch 1&3 and the record head selector switch 113 to position1 and it also releases the record relay 31A and the power relay 38B toremove power from the recording amplifiers 71 through 78 and from thecontrol mechanism 18. When the record reset relay 1'18 operates, itconnects the power line 2511 through a lead 235 and contact 2 of itsoperated armature 1 to a lead 233. The lead 238 is multipled to thethree terminals 2, 3 and 4- of the pole 1033 of the selector switch 103.The armature of the pole 103B simultaneously contacts four of the fiveterminals 1 through 5 at each position. With the record magazineselector switch 1'33 in position 5 at the end of the recording sequence,power is coupled through terminal 1 of the pole 103B to the winding ofthe selector switch 163 and the winding of the selector switch 113causing them to step from position 5 to position 1. As indicated above,the selector switches 103 and 1-13 are cyclically operated steppingswitches which successively step from position to position each timetheir windings are energized and which step from the last position atposition 5 to the first position at position 1 when energized atposition 5.

When the record magazine selector switch 103 steps to position 1, itsoperating power through terminal 10313 is open. A connection, however,is completed through the pole 10313 to terminal 5 thereof and thencethrough lead 23-2 and the operated armature 2 of the record reset relay118 to a lead 240. The energized lead 244 is connected to the groundedresistor 241 at one side of the record relay 31A and the power relay39B. The record relay 31A, as described above, was energized when therecord button 31 was closed, and the power relay 30 8 was energized whenthe power button 3% was closed. With potential at both sides of thewinding of the relays 31A and 39B, the relays 31A and 30B de-energ-izeand open respectively the armatures 31B, 31C, 30A and 36C. When thearmature 31B is opened, it opens the connection to the record amplifiers71 through 78, to the side tone amplifier 61 and to the biasingoscillator 62 causing them to return to normal. When the armature 31C isopened, it stops the clock lliT. When the armature NBC is opened, itde-energizes the motors 50, 51 and 52, and when the armature 36A isopened, it de-energizes the rest of the control mechanism 18. In thismanner, when the record reset relay 118 operates, it normalizes theselector switches 103 and -113 and it removes power from the controlmechanism 18 and from the electronic equipment 19.

The record reset relay 113 and the end of tape relay 127 remain operatedas long as the power button 39 is closed and the relay 30B is operated.The relays 118 and 127 release when, however, power is removed at theopen armature 3tiA. To initiate another recording sequence, themagazines 35 through 3?, inclusive, may be 9 changed or the magnetictapes 6% may be erased so that they can be utilized for anotherrecording sequence.

Normal Playback During the continuous recording sequence, informationwhich has already been recorded may be reproduced or played back.Information may also be played back after the continuous recordingsequence has terminated. The following sequence of operations occurswhen the information to be reproduced is in a magazine which is not thesame as the one being utilized for recording the input information. Thesequence of operations for recording and playing back from the samemagazine is subsequently described.

In order to initiate the normal playback sequence, the magazine which isto be reproduced is selected by the push buttons 11 through 15 and thedesired playback operation is selected by a playback mode switch 16. Thebuttons 11 through 15 and the switch 16 are both on the control panel 19(FZGURES 1 and The playback mode switc 16 has five positions 1 through 5which respectively are off, play, fast-forward, rewind and play-auto.For the normal playback sequence, the playback mode switch .16 is movedto its position 2, the play position. Let us assume that the magazine 37is receiving the input signals at the time that playback is initiated,and that information which was recorded on magazine 35 is to bereproduced. The playback buttons 11 through correspond respectively tothe magazines through 39. The lights 41 through 45 on the control panelalso correspond to the magazines 35 through 39 and provide indication ofwhich magazine is being utilized to record the input signals. The lamps41 through 45 are selectively energized over a path from the power lead291 through the pole 1631) of the switch 1% and cable 246 (FIGURE 7).With the magazine 37 being utilized, the switch 1&3 is in position 3 andthe light 43 on the control panel 16 is energized.

To select the magazine 35 for the normal playback sequence, the playbackbutton 11 is depressed. When the button 1-1 is depressed, it grounds apath from the power source 33 through armature 39A and a resistor 11Awhich is connected through a cable 243 to terminal 1 of the pole 102A ofa playback magazine selector switch 102. The armature oi the pole 132Ais connected to terminals 1 through 4 of the pole 191D of the playbackmode switch 1&1. The position of the playback mode switch is controlledby the switch 16 on the control panel 19. When the switch 16 is set toits position 2, the play position, as shown in PEGURE 5, it grounds apath from the power source 33 through the armature E'alA and a resistor16A which is connected through a cable 244 to terminal 2 of the pole161A. T he armature of the pole 191A is connected by the interrupter161T to the winding of the switch 161. The switches 1&1 and 1&2 stepwhen potential is removed from their windings. When the power relay SQBis operated, the windings of switches 1%]. and 192 are energized but theswitches do not step until the power is interrupted. When the switch 16moves from position 1 to position 2, it provides a pulse to the windingof switch 1&1 which step at the termination of the pulse to position 2.With the switch 161 at its position 2, the grounded connection throughthe pole lfiZA of the magazine selector switch 192 from the button 11 isextended to the winding of the selector switch lllZ causing it to hometo the position 1 if it is not thereat. The only one of the fiveterminals 1-5 of the pole 102A that is grounded is the terminal 1.

The tape control elements for the playback sequence are selected by thepoles 1%21-1, lllZI and 192K of the switch 192 and the operation mode isselected by the poles 191E, 19H and 161K of the switch Mill. The sixpoles 1%21-1, 1923, 162K, 181E, 161} and 161K actually perform the samefunction that the three poles 193E, 193- and lliSK of the magazineselector switch Hi3 performs for the recording sequence. The poles1631-1 and will control the energization of one of the rewind clutches35R through 39R; the two poles 1G2] and 13-15 control the energizationof one of the take-up clutches 35? through 39F and the two poles 1 32Kand lillK control the energization of one of the drive solenoids 358through 393.

Power is supplied to the armatures of the three poles "still-I, 1531!and 1&1 from the lead 251 over a path through the pole 16113 at position2, lead 247 and the normal armature of a playback interlock relay 112.Vr/ith the mode selector switch 1% at position 2 and the magazineselector switch 1G2 at position 1, power is supplied through the pole1611-1, a resistor 13%, the normal armature 3 of an advance relay 114,the normal armature 3 of a backspace relay 115, the pole 1921-1 andcable 349 to the rewind clutch 35R. The rewind clutch 35R is, in thismanner, energized to drive the take-up reel 34 to the magazine 35.Potential is provided through the pole 161], a resistor 131, the normalarmature '1 of the backspace relay 115, the normal armature of theadvance relay 114, and the pole 162 and the cable 350 to the take-upclutch 35F. The take-up clutch is, in this manner, energized to drivethe payout reel 33 of the magazine 35. Potential through the leads 2G1and 247 is also provided through the pole 13 1K, the normal armature 1of the backspace 115, the normal anmature 1 of the advance relay 1 14,the pole lilZK and cable 35-1 to energize the drive solenoid 358. Thedrive solenoid 35S rotates the pinch roller es of the magazine 35 toengage the tape 218 against the continuously rotating capstan as. Theoperating path to the drive solenoid 358 has a branch through a lead 717which is connected to the armature of the pole 132K. The lead 717 isconnected to a playback amplifier 7a in FIGURE 6 so that the amplifier7d becomes energized at the same time the tape is started. The operationof the amplifier 79 is hereinafter described.

With the clutches 35R and 35F energized and the drive solenoid 35Senergized, the tape 58 in the magazine 35 is moved adjacent a compositeplayback head 355 which is hereinafter described. As is also hereinafterdescribed, the advance relays 114 and 115 override the selected mode bythe playback mode switch 191 when they are energized.

in addition to selecting the magazine, one of the eight channels of themagazine tape may be selected or all eight channels may besimultaneously played back. The buttons 21 through 29 on the controlpanel Ill are utilized for selecting the playback channels. The buttons21 through 23, inclusive, control the position of a channel selectorswitch 117, and the button 29 controls the energization of a relay 119.The winding of a playback head selector switch 116 is connected inparallel with the winding of the playback magazine selector switch 115 2and is moved to the same position therewith. With the switch 192 atposition 1, to play back the signals, the switch 116 is, therefore, alsoat its position 1. The switch 116 controls the selection of thecomposite playback heads 359 through 354 (FIGURES 4 and 12). Theplayback composite heads 35% through 354 are similar to the compositeheads 21d through 214 which were briefly described above. The selectorswitch 116 selects 1 of the five playback heads 3% through 354 andestablishes eight connections from its eight heads '1 through 8 to thearmatures of the relay 119. As the relay 119 is operated, all eightreproducing heads of the selected composite head 35% are multiplied tothe playback amplifier 79, briefiy described above. The pla backamplifier 79 couples the amplified signals reproduced from the eightchannels to a speaker as. If the relay 119' is not energized and one ofthe buttons 21 through 23 is depressed, the switch 117 homes to the 11.selected position and the pole 1173 of the switch 1 17 establishes aconnection from the selected channel to the playback amplifier 7%. A lchannels or any one of the channels of any one magazine may, therefore,be reproduced.

At the end of the tape 68 of the magazine 35, the tape end switch 22%(FIGURE 10) is operated to provide potential through the cable 225,terminal 1 of the pole 11126, terminal 2 of the pole 161G, through thewinding of the interlock relay 112, lead 351 and terminal 2 of the pole191C to ground. When the relay 112 operates, it opens the path throughits armature to the playback mode poles 1M5, 1%313 and 1111K which, asdescribed above, couple power to the clutches 35R and 35F, to thesolenoid 35S and to the amplifier 79. The tape 68 in the magazine 35 isaccordingly halted when the interlock relay 1-12 is energized. The relay1-12 locks-operated over a locking path from the power lead 201 throughpole 161B, lead 247 and the operated armature of the relay 112.. Theother side of the winding of the relay 112 is grounded through the pole181C. As long as the playback mode selector switch 1111 remains atposition 2, the relay 112 remains energized. When the selector switch1&1 is stepped back to position 1, its oil position, by the playbackmode switch 16 on the control panel 19, the relay 112 is released.

T ape Advance Button 17 As described above, the advance relay 114 andthe backspace relay 1-15 override the mode selected by the switch 16 onthe control panel 1% when they are energized. The advance relay circuit114 and the backspace relay 115 are both controlled by a tape advancebutton 17 on the control panel 1% When the right side of the button 17is depressed, as viewed in FIGURE 1, a backadvance switch 17B, depictedin FIGURE 5, is closed and when the left side of the button 17 isdepressed, a forward-advance switch 17A is closed. When theforward-advance switch 17A is closed, it completes an operating pathfrom the power source 33 through the operated armature 30A of the powerrelay 3%13 through the switch 17A to the winding of the advance relay114. The switch 17B completes a similar path to energize the back--space relay 115.

When the advance relay 114 operates, it opens the operating path for therewind clutch 35R and for the drive solenoid 358 that were operatedduring the playback sequence. It also opens the power line through thelead 717 to the playback amplifier 79. The advance relay 114 and thebackspace relay 115 are only effective during the playback sequence.They do not perform any function with respect to the continuousrecording sequence and if a playback sequence is not taking place, theiroperation as described above, is non-functional. Assuming that theplayback sequence or" the magazine 35 is taking place, the operation ofthe relay 114 halts the advance under control of the drive solenoid 35Sand the rewind clutch 35R but maintains control by the take-up clutch35F. The operating paths for the drive solenoid 35S and the rewindclutch 35R are opened respectively at the armatures 1 and 3 of theadvance relay 114. The operating path for the take-up clutch 35F is nowfrom lead 247 through the normal armature of the interlock relay 112,the operated armatu e 2 of the advance relay 114 to the pole 1021.

The path through the operated armature 2 of the ad vance relay 114effectively shunts the resistor 13-1 to increase the power provided tothe take-up clutch 35F. The take-up clutch 35F, therefore, drives thetake-up reel 33 at a greater speed than its speed during the normalrecording or playback sequences. The advance relay 114- remainsenergized as long as the switch 17A on the control panel .10 is closed.When the switch 17A is opened, it releases the advance relay 114 torestore the original operating paths for the clutches 35R and 35F 12 andthe drive solenoid 35S. Normal playback thereupon continues.

When the backspace relay is energized, it opens the operating paths forthe take-up clutch 35F and for the drive solenoid 35S and it shunts theresistor 13% to increase the power delivered to the rewind clutch 35R.It also opens the power path to lead 717 and the playback amplifier 79.The power delivered to the rewind clutch is through the lead 247, thenormal armature of the interlock relay 112, the operated armature 3 ofthe backspace relay 115, the pole 10211 and cable 349 to the rewindclutch 35R. The paths to the take-up clutch 35F and to the drivesolenoid 358 are opened at the armatures 2 and 1 of the relay 115.

As longas the backspace relay 115 remains energized, the magnetic tape63 of the magazin'e 35 is rewound at a substantially rapid rate. Thegreater speed is achieved because the relay 115 eliectively shunts theresistor 130 which is serially connected with the rewind clutch 35Rduring the normal playback sequence. When the backspace relay =115 isreleased, the overriding rewind sequence terminates with the originaloperating paths for the clutches 35R and 35F and for the drive solenoid353 being restored.

In this manner, the advance relay 114 and the backspace relay 115 can beutilized to move the magnetic tape as of the magazine from whichinformation is beingreproduced either forward or back to any particularlocation. When the overriding control by the tape advance button 17 onthe control panel 10* terminates, the playback sequence automaticallyresumes with the tape signals being reproduced from the tape 68 at theportion which.

is positioned adjacent the associated playback heads at the terminationof the overriding control.

lie-Winding the Tape To rewind any of the tapes, the playback modeswitch 16 on the control panel 1%} (FIGURE 1) is moved to its position4, the rewind position, and one of the magazine selector buttons 11through 15 is depressed. Assuming that it is the tape 68 in the magazine35 which is to be rewound, the mode selector switch 15 is first turnedto its oil position so that the switch 101 homes to position 1. Bystepping the switch 181 to position 1, the interlock relay 112 isreleased it it is operated at this time. The switch 16 on the panel 10is thereupon moved to position 4 to move the selector switch 161 toposition 4. Power is provided through line 261, the pole 191B atposition 4, the normal armature of the relay 112, pole 1911-1 atposition 4, the normal armature 2 of relay 115, the normal armature 2 ofthe advance relay 114, pole 1921-1 at position 1, and through cable 345to the rewind clutch 35R. The connection to energize the rewind clutch35R shorts the resistor 1-30 so that a relatively large amount of poweris delivered to the clutch to rotate the payout reel 33 at a relativelyfast speed. The rewind sequence continues until the rewind tape endswitch 3&9 is operated. The rewind tape end switch 3641 is one of fiveswitches 36% through 364 which are similar to the tape end switch 22%through 224 but are operated by the opposite ends of the magnetic tapeses.

When the rewind tape end switch 360 is operated, it halts the rewindsequence by operating a rewind interlock relay 123. The operating pathfor the interlock relay 123 is from the switch 361 which is coupled toarmature 311A of the power relay 3113 for receiving power, and throughpole 1%? of the coincidence magazine selector switch v166 at positionlto the winding of the interlock relay 1-2-3. When the relay 12 3operates, it couples power from the cable 20 1 through its operatedarmature to the winding of the record search relay which, however, doesnot operate at this time. The operation of the relay EtZtB ishereinafter described.

The rewind tape end switch 366, however, is also connected together withother tape end switches 361 through 13 364 to the winding of an endrewind relay 369 which operates. When the relay 369 operates, itinterrupts at its armature 2, the operating path for the rewind clutch35R bringing the magnetic tape 68 in the magazine 35 to a halt. Therelay 369 also locks through its operated armature 1, lead 379, terminal4 of the pole 111'1L, the normal armature of the interlock relay 112,lead 247 and pole 10113 to the power lead 201. In this manner, it theswitch 101 is set at position 4 for a rewind sequence, the rewind relay369 locks-operated to halt the rewind sequence of the magnetic tape 68in the magazine 35. In the event that the magnetic tape 68 is beingrewound, for example, during a playback operation under control of thebackspace relay 115 in a manner described above, the relay 369 does notbecome locked-operated because the pole 1ii1L is not at position 4.

Recording and Playback f the Same Magazine The normal playback sequencedescribed above, was for playing back signals recorded in one of themagazines 35 through 39 at the same time that input signals were beingrecorded in a different one of the magazines 35 through 39. In the eventit is desired to reproduce or playback signals recorded in a magazinewhich is being utilized for recording the input signals, the recordingsequence is transferred to the standby magazine 39. To initiate thesequence, one of the playback buttons 11 through 15 is depressed to homethe playback magazine selector switch 102 to the position indicated bythe depressed magazine selector button. The playback mode switch 16 onthe control panel 1%} is also moved to position 2, the play position.The selector switch 102 homes to the position indicated by the depressedmagazine selector button over an operating path described above throughthe poles 1112A and 101D.

The lamps 41 through 45 on the control panel 11 as described above,provide a visual indication of the identity of the magazine which isrecording the input signals. By depressing one of the playback buttons11 through 15 which corresponds with the energized one of the lamps 41through 45, a coincidence sequence is initiated for transferring theinput signals to the standby magazine 39. A coincidence between therecording and playback magazines occurs when the magazine selectorswitches -3 and 102 are at the same position. The switch 103 selects themagazine for recording and the switch 102 selects the magazine forplayback. If the switch 192 is positioned at the same position as theswitch 1113 by the playback buttons on the control panels, a coincidencesequence selector switch 104 is stepped to provide an indication of thecoincidence between the magazine which is recording the input signalsand the magazine from which the reproduction of signals is desired.Assume, for example, that the magazine 35 is still recording the inputsignals and that the playback button 11 on the control panel v1t} isdepressed to initiate a playback sequence of information, reproduced inthe magazine 35. The coincidence sequence selector switch 104 isoperated over a path from the power line 261, through the pole 103D atposition 1, through the pole 1112B also at the position 1, through thepole 131E at position 2, through lead 380, pole 134D at position 1, pole164A also at position 1, through the interrupter 104]) to the winding ofthe switch 104. The switch 104 accordingly steps from its normalposition 1 to its position 2.

When the switch 104 steps to position 2, it homes the record coincidencemagazine selector switch 166 to the position of coincidence to registeran indication of the magazine identity. With the magazine 35 being thecoincidence magazine, the switch 186 is horned to position 1. Theoperating path for the switch 1136 is from the power line 201 throughlead 381, pole 104C at position 2, lead 382, to the pole 19213 atposition 1, through the cable 384 to terminal 1 of the pole 106A. Thepole 106A includes a multi-contact armature which contacts four of thefive terminals at each position. In the position shown in FIGURE 7, anoperating path is not completed from terminal 1 to the winding of theswitch 166. The switch 106 accordingly remains at its position 1. If theswitch 106 were in any other position at this time, it would home to itsposition 1 because it would continue to step as long as power wascoupled through its terminal 1 at its armature to its winding. At anyposition of the switch 196 except the position 1, the armature of thepole 1116A couples the operating potential to the winding of the switch106.

When the coincidence switch 104 steps to its position 2, it alsofunctions to record a 1 kilocycle tone in the first channel of the tape63 in the magazine 35- which is still recording the input signals. Thepower line 201 is coupled through the lead 381, pole 1114C at position2, and pole 104E also at position 2, to the power lead 385 which iscoupled to the oscillator 379. The oscillator 371} is a 1 kilocycleoscillator which is coupled to the input of the recording amplifier 71.As described above, the recording amplifier 71 is one of eightamplifiers 71 through 78 which respectively couple the input signals tothe eight recording heads of one of the composite heads 210 through214-. The composite heads 21% through 214 are selected in accordancewith the position of the selector switch 113, and, as indicated above,this switch is operated in parallel with the magazine selector switch103. Accordingly, the selector switch 113 is at position 1 to utilizethe composite head 21% which is coupled to the magnetic tape 63 of themagazine 35. The '1 kilocycle tone from the oscillator 370 is amplifiedby the recording amplifier 71 and the amplified tone is coupled throughthe pole 113A at position 1 to the recording head 1 of the compositehead 210. The '1 kilocycle tone is accordingly recorded in the firstchannel of the magnetic tape 68 in the magazine 35.

At the same time that the coincidence switch 1114 functions to recordthe 1 kilocycle control signal in the magazine 35, it initiates a homingoperation of the magazine selector switch 103 to transfer the recordingsequence to the magazine 39.

The operating path for the record magazine selector switch 103 is fromthe power line 201 through the lead 381, the pole 104C at position 2,armature 1 of the record reset relay 118 :Which is normal at this time,through lead 238 to terminals 2, 3 and 4 of the pole 103B of theselector switch 1113. The armature of the pole 10318 is a multiplecontact armature which; simultaneogusly contacts four of the fiveterminals 1 through 5 of the pole 1633 at any position. With themagazine selector switch 103 initially at position 1, the armature ofthe pole 193B is positioned as shown in FIGURE 8. The potential from thepower line 201 is, therefore, coupled through the pole 11138 when theswitch 1153 is at position 1, through lead 388, pole 10413 at position'2 and lead 228 to the winding of the selector switch 1113. The switch163 accordingly steps to position 2. At position 2, the pole 1033 alsocoupled the stepping potential to the winding of the selector switch1113. The switch .1153 accordingly steps repeatedly until position 5 isreached. At position 5, the (homing sequence is halted.

The record head selector switch 113 is operated in parallel, asdescribed above, with the magazine selector witch 1&3 so that theamplified input signals from the recording amplifiers 71 through 78 arenow introduced to the composite recording head 214 instead of to thecomposite recording head 210. During the homing operation, the magazine3-5 is de-energized because the operating paths to the take-up clutch35F to the rewind clutch 35R and to the solenoid 3-58 are respectivelyinterrupted at the poles 10311, 1113-] and 1113K. These operating pathswere described above during the continuous recording sequence. When theswitch 103 is stepped to position 5, the poles 1031-1,- 163] and 103Know couple operating potential received through leads 201 and 201}respectively to the clutches 39R and 39? and to the drive solenoid 395.The'recording sequence is, in this manner, transferred from the magazine35 to the magazine 39, after'the 1 kilocycle control signal is recordedin the first .channel of the magnetic tape 68 in the magazine 35.

With switch 103 in position 5, the coincidence switch 1% is stepped toits position 3. The operating path for the switch 1% is from the powerline 2&1 through the pole 1fi3E, now at position 5, lead 3% and the pole184A at position 2 to the winding of the switch 1134. The switch 164accordingly steps from position 2 to position 3. With the switch 113 inposition 3, and the input signals now being recorded in the standbymagazine 39, the signals previously recorded in the magazine 35 can nowbe played back in accordance with the normal playback sequence describedabove. With the playback mode selector in position 2, the play position,the backspace relay 115 and the advance relay 114 are effective to movethe magnetic tape as in the magazine 35 backward or forward to anyparticular position from which it is desired to play back the recordedsignals. The input information continues to be recorded in the standbymagazine 3 until the playback mode switch 1%1 is stepped to its position1, the off position, or until the playback magazine selector switch 182is stepped to a diiierent position by one of the playback buttons 11through 15 to terminate the coincidence described above between therecording and playback sequences.

When the playback mode switch 16 on the control panel 10 is moved to itsoff position, the selector switch 191 steps back to position 1 tocomplete a path from the power line 29 1, through the pole 1 .1113, nowat position I, lead 392, and pole 134A at position 3 to the winding ofthe switch 11%. The coincidence sequence selector switch 1% accordinglysteps from position 3 t position 4. If one of the playback buttons 12through 15 is operated so that anti-coincidence is indicated, anoperating path is also completed [for stepping the coincidence switch134 from position 3 to position 4 from the power line 2&1 through thepole 102C at a position corresponding to the depressed buttons 12through 15 on the control panel 19, cable 3&3, the pole H563 to the pole194A at position 3. If there is a coincidence, power is not provided tostep the switch Hi4 but if there is an anti-coincidence between thepoles 1%120 md 1363, potential is coupled through the poles 162C and19613 to the pole 104A causing the switch 1% to step. In this manner, ifeither the playback mode switch 191 is returned to position 1 or if themagazine selector switch 1&2 is stepped to a diiferent position(diiferent from position 1) the switch 164 is operated to initiate atransfer sequence 'for returning the input signals to the magazine 35instead of to the standby magazine 39.

The same operating path for stepping the coincidence selector switchlit-t from its position 3 to its position 4 is extended through a lead396 (FIGURE 8), through pole oF, still at position 3, lead 398 and pole113 5 at position 1 t0 the winding of the tape search selector switch115. At the same time, therefore, that the co incidence selector switch1&4 is stepped to position 4, the tape search selector switch 1% isstepped from its position 1 to its position 2. As is hereinafterdescribed, the tape search selector switch 1%5 functions to locate thetermination of the 50 cycle control signal continuously recorded in thefirst channel of the magazine 35 with the input signals so that therecording sequence can be continued at that point on the magnetic tape68.

When the switch 195 steps to position 2, it connects a control amplifier122 to the recording head 1 of the composite head 21% associated withthe magazine 35 and it initiates a rewind sequence of the tape 68 in themagazine 35. The recording head 1 of the composite head 210 is utilizedas a playback head to locate the 50 cycle tone continuously recorded onthe magnetic tape 68 together with the. input signals in the magazine35. Actually arouses because of the high speed reeling during rewind,the eiiective frequency 5(} cycle tone is much higher than 50 cycles persecond; The rewind speed may be 8 times as great as the recording speedof 1.7/3 inches e second so that an effective frequenc of 1000 cyclessecond is reproduced. The amplifier 22 is a tuned ampiifier having abandpass which includes 1060 cycles per second. During the search forthe stepped 7!} control tone, the recording sequence continues with theinput signais being provided to the standby magazine 39. The recordinghead 1 of the composite head 21%: is coupled through a cable 272, pole166E at position 1 to indicate the original coincidence and pole lfi'SE,now at position 2, to the control amplifier 122.

The tape search switch 1115 also connects the output of the controlamplifier 122 across the record search relay 129. The operating path forthe relay 120 is through the pole 1858 at position 2. The controlamplifier 122 has two output terminals, one coupled directly to thewinding of the relay 12G and the other coupled to the armature of thepole 1%53. When the control amplifier 122 detects the continuouslyrecorded control signal, it accordingly operates the record search relay12s to provide an indication of the control signal detection.

As indicated above, the tape 68 in the magazine 35, which was themagazine originally utilized for recording the input signal, is rewoundwhen the search selector switch 195 steps to position 2. During thesearch interval, the path for supplying power to the rewound clutches55R is from the power line 201 through the pole H at position 2, thepole 1%H, still at position 1, and the normal armature 2 of the relay359 to the rewind clutch 35R. The control amplifier 122 searches for thecontrol tone during the rewind sequence of the magazine 35. The rewindsequence continues until the tone is detected and the record searchrelay 12% is operated. At the same time that the relay 12s operates, thetape search selector switch 105 is stepped from its position 2 to itsposition 3. The operating path for the switch 165 is from the outputterminal 122A of the amplifier 122, pole 10513 at position 2, pole 105Aat position 2 to the winding of the switch 165. The switch 195, in thismanner, steps to its position 3 at the same time that the relay 12%operates to indicate the detection of the control tone in the magazine35. By the time the switch 105 steps, the position on the magnetic tapeupon which the control tone ends or terminates has been rewound on thepayout reel of the magazine 35. When the switch 105, however, steps fromposition 2 to position 3, it removes power from the rewind clutch 35Rand it provides power to the take-up clutch 35F so that the magazine 35goes into a fast-forward operation to locate the end of the controltone. At the end of the control tone, the control amplifier 122 releasesthe relay 120. When the relay returns to its normal condition, it stepsthe switch 105' from position 3 to position 4 to halt a tape at the endof the recorded tone. The switch 105 is stepped to position 4 when therelay 120 releases over a path from lead 281 (FIGURE 10), the normalarmature of the take-up relay 125, lead 399, the normal armature 1 ofrelay 126 and pole 105A at position 3 to the winding of switch 195. Whenthe pole 1051 of the switch is stepped to position 4, it opens the pathfor supplying power to the take-up clutch 35F so that the tape 68 in themagazine 35 is halted. 7

When the switch 105 steps to position 4, it also functions to record the1 kilocycle tone on channel 1 of the magazine 39. The power is providedfrom the power line 201 through the pole 104C at position 4, pole 106Cat position 1 to indicate the original coincidence, pole 103C atposition 5, pole 105C, now at position 4, pole 104E at position 4 andthe oscillator 3 70 to the recording amplifier 71. The recordingamplifier 71 is coupled through pole 113A at position 5 to the recordinghead 1 of a composite head 21 The composite head 214 is per 17magnetically coupled to the tape 68 in the standby magazine 39.

At the same time that the l kilocycle control signal is recorded in themagazine 39, a homing operation is initiated for returning the selectorswitch 103 and the selector switch 113 back to position 1 for recordingthe input signals in the original magazine 35. The homing path for theswitches 103 and 112 is from the power line 201 through the lead 381,pole 1040 at position 4, pole 106C at position 1, pole 103C at position5, lead 401, pole 1050 at position 4 and lead 228 to the windings of theswitches 103 and 113. When the switches 103 and 113 step from position 5to position 1, the recording sequence of the input signals istransferred from the magazine 39 back to the magazine 35. The clutches39R and 39F and the solenoid 393 are de-energized and the clutches 35Rand 35F and the solenoid 355 are energized over paths through the poles1031-1, 103] and 103K. These operating paths were described above duringthe continuous recording sequence.

When the switch 103 returns to its original position, the position 1, toselect again the magazine 35, its position coincidence with that of theswitch 105 causes the search switch 105 to step from position 4 back toposition 1 to ready it for the next cycle of operation. The operatingpath for the switch 105 is from the power line 201 through the pole 103Dat position 1, the pole 106D at position 1 and the pole 105A at position4 to the winding of the switch 105. 'With the switch 105 back inposition 1, the control mechanism 18 is back in its original recordingcondition and the recording sequence continues in the normal manner. Forexample, when the end of the magnetic tape 68 in the magazine 35 isdetected, the recording signals are automatically transferred to themagazine 36.

During the searching operation for the continuously recorded 50 cyclecontrol signal, in order to return the recording sequence back to theoriginal magazine, if the terminating end of the tape 68 in the magazine35 is reached, the interlock relay 125 is operated to couple operatingpotential through a lead 403 to the pole 105A which is at position 3duringthe fast-forward operation. The switch 105A accordingly steps toposition 4 to initiate the return transfer sequence from the magazine 39to the magazine 35. When the switch 103 homes to position 1, it steps toposition 2 under control of the tape end switch 220 just as in thecontinuous recording sequence. The switch 220 completes a path overcables 225 and 226 to step the switch 103. The recording sequence,therefore, recommences at magazine 36-.

The 1 kilocycle tones recorded on the tape 68 before a transfer of theinput signals to another tape are utilized during the automatic playbacksequence. As is hereinafter described, the 1 kilocycle tones function toswitch the playback sequence back and forth to the standby magazine 39so that the reproduced signals are continuous and in the orderintroduced to the recording apparatus. The 1 kilocycle tones are noteffective during the searching operation for the end of recorded signalson the original tape as it is the 50 cycle continuous tone stepped up to1 kilocycle by the high speed reeling which is effective.

During the continuous recording sequence described above, the signals tobe recorded were successively introduced to all five magazines 35through '39. If the standby magazine 39 is not required for anycoincident playback sequence of the type just described, ten hours ofinput signals may be recorded with two hours in each of the fivemagazines 35 through 39. If a portion of the tape 68 in the magazine 39is utilized for coincident playback sequences, the total continuousrecording sequence has a duration less than ten hours but at least ofeight hours. Suppose, for example, that approximately /2 of the tape 68in the magazine 39 has been utilized for recording input signals. Duringthe continuous recording sequence when the end of the tape 68 in themagazine 38 is reached, the selector switch 103 is stepped to position 5to select the magazine 39. The tape 68 in the magazine 39, however, isnot positioned at its beginning adjacent the recording head 214 but ispositioned at a point at which it was stopped at the end of the lastcoincident playback sequence. The tape 68 in the magazine 3-9 is notrewound during the coincident playback sequences. The maximum duration,therefore, of the cont-inuous recording sequence depends upon the numberand durations of coincident playback sequences.

Automatic Playback At the completion of the continuous recordingsequence, it may be desired to play the entire recorded information insequence without intersplicing the tape in the magazine 39. The lkilocycle tone, which was recorded at two switching points for eachcoincident playback sequence, is utilized to control the automaticplayback sequence in the same order as during the recording sequence. Toinitiate the automatic playback sequence, the mode switch 16 on thecontrol panel 10 is first moved to position 2, the play position, andthe magazine selector button 11 is depressed. Any one of the magazinesmay be utilized for the starting point but usually the first magazine3-5 is utilized for initiating the au tomatic playback sequence.

When the switch 16 on the control panel 10 is turned to the automaticplay position, the mode selector switch 101 is horned to position 5.When the switch 102 is stepped to position 1 under control of the button11, an automatic playback memory switch 107 is also stepped toposition 1. The operating path for the switch 107 is from the power line201 through the normal armature 2 of an automatic transfer relay 108,the pole 102E at position 1, the armatures of an automatic playbackselector relay 109, the pole 11073, and the normal armature 3 of therelay 108 to the winding of the switch 10-7. The switch 107 steps whenits winding is de-energized which occurs when the position of the poles10713 and 102E in the operating path match.

When the switch 101 is moved to position 5, it closes a control pathfrom the line 201 through the pole 101B for operating the transfer relay108 to disconnect the magazine selection buttons 11 through \15 and toswitch the homing circuit to the winding of the switch 102. The controlpath is through the poles 101D, 101B, 10213 and the armatures of thetransfer relay 108. The winding of switch .103, the magazine selectorswitch, is connected through pole 1043 at position 1, pole 103A atposition 1, pole 107A at position 1 and the operated armature 3 of relay108 to the winding of relay 107. When the switch 107 is thereafterstepped, the switch 107 steps therewith. Playback continues in thenormal manner in the magazine 35 until a l kilocycle tone appears and isdetected through the pole E by the control amplifier 122. The controlamplifier 122 recognized the 1 kilocycle tone as well as the higherfrequency tone developed during rewind and fast-forward. The controlamplifier (122 operates a playback sequence relay over a path throughthe pole 10513.

When the playback sequence relay 110 operates momentarily by theamplifier 122, it homes the switch 102 to the magazine 30 through thearmatures of the switch 108 instead of to the magazine 35. When relay110 operates, it completes a path from the power line 20 1 through theoperated armature of relay 110 to the wind ing of relay 109. The relayi109 is a bistable relay which remains operated until the next momentaryoperation of the relay .110. When the relay .109 operates, it connectspower from line 201 through the operated armature 2 of relay 103, theoperated armatures 1-4 of relay .109, the contacts 14 of pole 102E, theoperated armature 1 of relay 108 and pole 101D at position 5 to theWinding of the switch 102. The switch 102 accordingly homes or steps toposition 5.

1. A RECORDING AND REPRODUCING APPARATUS, INCLUDING, A PLURALITY OFINDIVIDUALLY MOVABLE RECORDING MEDIUMS, A PLURALITY OF TRANSDUCERMEMBERS INDIVIDUALLY POSITIONED ADJACENT SAID PLURALITY OF RECORDINGMEDIUMS FOR INTRODUCING SIGNALS TO BE RECORDED TO SAID PLURALITY OFRECORDING MEDIUMS, FIRST MEANS FOR SUCCESSIVELY MOVING SAID RECORDINGMEDIUMS AND FOR INTRODUCING THE SIGNALS TO BE RECORDED TO SAIDTRANSDUCING MEMBER WHICH IS POSITIONED ADJACENT THE MOVING ONE OF SAIDMEDIUMS, SECOND MEANS FOR REPRODUCING SIGNALS RECORDED ON ANY ONE OFSAID PLURALITY OF RECORDING MEDIUMS WITHOUT DISTURBING THE OPER-